diff --git a/openhis-server-new/openhis-application/src/main/java/com/openhis/web/regdoctorstation/appservice/impl/RequestFormManageAppServiceImpl.java b/openhis-server-new/openhis-application/src/main/java/com/openhis/web/regdoctorstation/appservice/impl/RequestFormManageAppServiceImpl.java
index 1ad8ec3c6..18736f832 100755
--- a/openhis-server-new/openhis-application/src/main/java/com/openhis/web/regdoctorstation/appservice/impl/RequestFormManageAppServiceImpl.java
+++ b/openhis-server-new/openhis-application/src/main/java/com/openhis/web/regdoctorstation/appservice/impl/RequestFormManageAppServiceImpl.java
@@ -162,11 +162,15 @@ public class RequestFormManageAppServiceImpl implements IRequestFormManageAppSer
             serviceRequest.setEncounterId(encounterId); // 就诊id
             serviceRequest.setAuthoredTime(curDate); // 请求签发时间
 
-            Long positionId = activityOrganizationConfig.stream()
-                .filter(dto -> activitySaveDto.getAdviceDefinitionId().equals(dto.getActivityDefinitionId()))
-                .map(ActivityOrganizationConfigDto::getOrganizationId).findFirst().orElse(null);
+            // 优先使用前端传来的 positionId（用户手动选择的发往科室），未传时从配置表查找
+            Long positionId = activitySaveDto.getPositionId();
             if (positionId == null) {
-                throw new ServiceException(activitySaveDto.getAdviceDefinitionName() + "未配置当前时间段的执行科室");
+                positionId = activityOrganizationConfig.stream()
+                    .filter(dto -> activitySaveDto.getAdviceDefinitionId().equals(dto.getActivityDefinitionId()))
+                    .map(ActivityOrganizationConfigDto::getOrganizationId).findFirst().orElse(null);
+                if (positionId == null) {
+                    throw new ServiceException(activitySaveDto.getAdviceDefinitionName() + "未配置当前时间段的执行科室");
+                }
             }
             serviceRequest.setOrgId(positionId); // 执行科室
 
diff --git a/openhis-ui-vue3/src/views/inpatientDoctor/home/components/order/applicationForm/laboratoryTests.vue b/openhis-ui-vue3/src/views/inpatientDoctor/home/components/order/applicationForm/laboratoryTests.vue
index 03d3a205d..4324bd8b8 100755
--- a/openhis-ui-vue3/src/views/inpatientDoctor/home/components/order/applicationForm/laboratoryTests.vue
+++ b/openhis-ui-vue3/src/views/inpatientDoctor/home/components/order/applicationForm/laboratoryTests.vue
@@ -164,7 +164,7 @@ onMounted(() => {
  * type(1：watch监听类型 2:点击保存类型)
  * selectProjectIds(选中项目的id数组)
  * */
-const projectWithDepartment = (selectProjectIds) => {
+const projectWithDepartment = (selectProjectIds, type) => {
   //1.获取选中的项目 2.判断项目的执行科室是否相同 3.判断执行科室是否配置 4.将项目的执行科室复值到执行科室下拉选位置
   let isRelease = true;
   // 选中项目的数组
@@ -225,9 +225,13 @@ const submit = () => {
   if (transferValue.value.length == 0) {
     return proxy.$message.error('请选择申请单');
   }
+  // 🔧 Bug #516: 捕获用户手动选择的发往科室，避免 projectWithDepartment 将其覆盖为默认科室
+  const savedTargetDept = form.targetDepartment;
   if (!projectWithDepartment(transferValue.value, 2)) {
     return;
   }
+  // 用户手动选择的发往科室优先于项目默认执行科室
+  const targetDept = savedTargetDept || form.targetDepartment;
   let applicationListAllFilter = applicationListAll.value.filter((item) => {
     return transferValue.value.includes(item.adviceDefinitionId);
   });
@@ -238,7 +242,7 @@ const submit = () => {
       unitCode: item.priceList[0].unitCode /** 请求单位编码 */,
       unitPrice: item.priceList[0].price /** 单价 */,
       totalPrice: item.priceList[0].price /** 总价 */,
-      positionId: item.positionId || form.targetDepartment, //执行科室id，未配置时使用用户手动选择的科室
+      positionId: targetDept || item.positionId, // 用户指定发往科室优先于项目默认执行科室
       ybClassEnum: item.ybClassEnum, //类别医保编码
       conditionId: item.conditionId, //诊断ID
       encounterDiagnosisId: item.encounterDiagnosisId, //就诊诊断id